The use of seton as a bridge to definitive ligation of the intersphincteric fistula tract procedure for fistula-in-ano: a systematic review and meta-analysis

Background: There is still controversy over the usefulness of seton placement prior to the ligation of the intersphincteric fistula tract (LIFT) surgery in the management of anal fistula. Objective: To evaluate the impact of preoperative seton placement on the outcomes of LIFT surgery for the management of fistula-in-ano. Design: systematic review and meta-analysis. Data Sources: A search was performed on the MEDLINE (PubMed), EMBASE, Scopus, Web of Science, Cochrane Library and Google Scholar databases. Study Selection: Original studies without language restriction reporting the primary healing rates with and without seton placement as a bridge to definitive LIFT surgery were included. Intervention: The intervention assessed was the LIFT with and without prior seton placement. Main Outcome Measures: The main outcome was defined as the primary healing rate with and without the use of seton as a bridge to definitive LIFT surgery. Results: Ten studiesmet the criteria for systematic review, all retrospective,with a pooled study population of 772 patients. There were no significant differences in the percentages of recurrence between patients with and without seton placement (odds ratio [OR] 1.02; 95% confidence interval [CI] 0.73-1.43: p=0.35). The I2 value was 9%, which shows the homogeneity of the results among the analyzed studies. The 10 included studies demonstrated a weighted average overall recurrence of 38% (interquartile range [IQR] 27-42.7%), recurrence with the use of setonwas 40%(IQR26.6-51.2%), and without its use, the recurrence rate was 51.3% (IQR 31.3-51.3%) Limitations: The levels of evidence found in the available literature were relatively fair, as indicated after qualitative evaluation using the Newcastle-Ottawa scale and the Attitude Heading Reference System (AHRS) evidence levels. Conclusions: Our meta-analysis suggests that the placement of seton as a bridge treatment prior to LIFT surgery does not significantly improve long-term anal fistula healing outcomes. Ligation of the intersphincteric fistula tract surgery can be performed safely and effectively with no previous seton placement. International prospective register of systematic reviews-PROSPERO registration number: CDR42020149173. (AU)

Local irrigation with silver nitrate, a non-surgical approach for persistent anal fistula / Irrigação local com nitrato de prata, uma abordagem não cirúrgica para fístula anal persistente

ABSTRACT Purpose: Treatment of persistent anal fistula implies a major challenge for surgeons, with risk of additional recurrence and potential continence impairment. We present a non-surgical treatment based on irrigation with silver nitrate 1% solution. Methods: This is a prospective study including patients with persistent anal fistula after surgery, who were treated with silver nitrate 1% solution irrigation from May 2015 to March 2017. Patients with evidence of abscess, presence of >1 external opening and those with bowel inflammatory disease were excluded. 3-5 cc of silver nitrate 1% solution were instilled through a catheter. The procedure was repeated on a weekly basis, conducting a maximum of 7 sessions per patient. Results: 18 patients (13 male, 72.2%) with a median age of 48 years old (IQR 41-55) were treated using silver nitrate 1% solution. A median of 5 sessions per patient was performed (IQR 3-6). The median follow-up period was 18 months (IQR 9-25). After the described period 8 patients' (44.4%) presented complete resolution of the fistula, 2 patients' (11.2%) were classified as partial healing and in 8 patients' (44.4%) the treatment was considered to fail. 6 patients' experienced self-limited pain during instillation, with persistence up to 24 h in 2 of them. Conclusions: Treatment with silver nitrate 1% solution is a minimally invasive procedure, with a favourable safety profile, that can be performed in an outpatients' basis achieving a complete healing rate of 44.4%. Therefore, this method should be considered for the treatment of recurrent or persistent anal fistula.

RESUMO Objetivo: O tratamento da fístula anal persistente é um grande desafio para os cirurgiões, com risco de recorrência adicional e potencial comprometimento da continência. Os autores apresentam um tratamento não cirúrgico baseado na irrigação com solução de nitrato de prata a 1%. Métodos: Este foi um estudo prospectivo incluindo pacientes com fístula anal persistente após a cirurgia que foram tratados com irrigação com solução de nitrato de prata a 1% entre maio de 2015 e março de 2017. Pacientes com evidência de abscesso, presença de mais de uma abertura externa e aqueles com doença inflamatória intestinal foram excluídos. Usando um cateter, instilou-se 3 a 5 cc. de solução de nitrato de prata a 1%. O procedimento foi repetido semanalmente, em um máximo de sete sessões por paciente. Resultados: Um total de 18 pacientes (13 homens, 72,2%) com idade mediana de 48 anos (IQR 41-55) foram tratados com solução de nitrato de prata a 1%. Uma mediana de cinco sessões por paciente foi realizada (IQR 3-6). A mediana do período de acompanhamento foi de 18 meses (IQR 9-25). Após o período descrito, oito pacientes (44,4%) apresentaram resolução completa da fístula, dois pacientes (11,2%) foram classificados como cicatrização parcial e em oito pacientes (44,4%) o tratamento falhou. Seis pacientes apresentaram dor autolimitada durante a instilação, que persistiu por até 24 horas em dois deles. Conclusões: O tratamento com solução de nitrato de prata a 1% é um procedimento minimamente invasivo, com perfil de segurança favorável, que pode ser realizado em regime ambulatorial, atingindo taxa de cura completa de 44,4%. Portanto, este método deve ser considerado para o tratamento da fístula anal recorrente ou persistente.